How long does a typical project take?

Timelines vary by scope. A small web app takes 4-8 weeks, a medium full-stack project 2-4 months, and enterprise-grade systems 4-8 months. As a freelance developer, I provide a detailed timeline during the Discovery phase and keep you updated at every sprint.

Do you work with startups or only enterprises?

I work with everyone — from early-stage startups building their MVP to established enterprises modernizing their systems. As a freelance developer, my flexible engagement models adapt to your needs and budget. I'm especially passionate about helping startups launch their first product.

What happens after the project is launched?

Every project includes post-launch support (duration depends on the scope). I handle bug fixes, monitoring, and minor updates. For ongoing needs, I offer freelance retainer packages and dedicated hourly/monthly arrangements.

How do you ensure code quality?

Every line of code goes through peer code reviews, automated testing (unit + integration), linting, and security scans. I follow clean architecture principles and industry best practices. As a freelance developer, my reputation depends on the quality I deliver.

Can you work with our existing team?

Absolutely. I offer staff augmentation, pair programming, and consulting models where I integrate directly with your team. I adapt to your tools, processes, and communication channels. Many clients hire me as a freelance extension of their in-house team.

What technologies do you use?

I specialize in Java, Spring Boot, React, Next.js, TypeScript, PostgreSQL, Redis, Docker, Kubernetes, and Kafka. But I choose technologies based on what's best for your specific project, not one-size-fits-all.

How do I hire you as a freelance developer?

Simply reach out via the contact form or email. We'll start with a free 30-minute consultation to understand your project. I'll then provide a detailed proposal with timeline, cost, and approach. You can hire me for fixed-price projects or on an hourly/monthly basis.

What are your freelance rates?

Every project is unique, so I provide custom quotes based on scope, complexity, and timeline. I offer competitive freelance rates for startups and businesses of all sizes. Contact me for a free estimate — no obligation.

Do you offer ongoing freelance support and maintenance?

Yes! I offer flexible freelance retainer packages for ongoing development, maintenance, monitoring, and feature additions. Many of my clients maintain long-term freelance relationships for continuous product evolution.

Do you sign Non-Disclosure Agreements (NDA) and transfer IP rights?

Yes, 100%. I sign a strict NDA before discussing sensitive project details. Upon full payment, 100% of the intellectual property (IP) rights, source code, design files, and deployment assets belong entirely to you.

Back to Portfolio

Retail8+ technologies

KeepComing - Digital Loyalty Platform for Independent Shops

Live / Paid CustomersProduct Status

Apple + GoogleWallet Platforms

<15sOnboarding Time

$19–$79/moPricing Plans

The Challenge

Small independent businesses — cafes, restaurants, salons, barbers, retail shops — run on regulars. The paper punch card is the oldest, most reliable retention tool in that world, and also the most fragile: cards get lost, forgotten, or thrown in a drawer. Every existing digital alternative asked customers to download yet another app, which is exactly the friction that kills adoption at the counter. KeepComing set out to build something a customer could opt into in under fifteen seconds, with no download, no account setup, and no card to lose, using infrastructure they already carry: Apple Wallet and Google Wallet. It also targeted a segment most SaaS loyalty tools ignore, independent shops, because average revenue per customer is too small for enterprise sales motions.

The Solution

I built a multi-tenant SaaS platform on a Next.js frontend and NestJS backend, with PostgreSQL for data, Redis and BullMQ for background jobs, and real integrations with Apple PassKit and the Google Wallet API — the two hardest technical pieces, and the ones most SMB loyalty tools skip. A shop signs up in minutes, sets a reward, and gets a QR code; customers scan it, add the card to Apple Wallet or Google Wallet in one tap, and every visit pushes a real-time update to the card already on their phone. On top of that core loop: multi-channel delivery via QR, link, WhatsApp (WhatsApp Business API), and email; birthday and reward automations that fire on their own once a shop sets the rules; staff scan pages that work from any phone camera with no extra hardware; an owner-facing analytics view for visits, top customers, and redemption patterns; and a native mobile app so shop owners can manage their program on the go. The platform was also built as an ecosystem from day one — a public, versioned developer API and documentation, plus a partners program for agencies, resellers, and technology partners — treating our own frontend as just one client among many.

Key Features

Real Apple Wallet & Google Wallet integration with real-time card updates

Zero-download onboarding — customers join in under 15 seconds via QR scan

Multi-tenant architecture with fully isolated customer, staff & analytics data

Birthday & reward automations, staff scan pages, and owner analytics dashboard

Multi-channel delivery: QR, link, WhatsApp, and email

Public developer API, documentation & partners program for third-party integrations

Native mobile app for shop owners to manage loyalty on the go

The Outcome

KeepComing is live at www.keepcoming.app with paid customers in production, running real Apple Wallet and Google Wallet integration on both iPhone and Android with real-time updates. It ships a public developer API and documentation so third-party integrations are supported rather than blocked, and runs on a three-tier pricing model with a 14-day, no-credit-card trial.

Visit Live Site ↗

Tech Stack

Next.jsNestJSPostgreSQLRedisBullMQApple PassKitGoogle Wallet APIWhatsApp Business API

Client Testimonial

“”

Like What You See?

Let's build something great together.

More Work

View all projects

AI / Technologygenekogan.com

EDEN - Autonomous Creative AI Studio

The generative AI space is dominated by single-shot prompt-and-response tools: type a prompt, get an image, close the tab. Eden set out to build something more ambitious: a platform where creators could build persistent, autonomous AI agents with their own personalities, their own custom-trained visual models, and the ability to collaborate with humans and with each other on multi-step creative work. That meant solving problems the space doesn't have textbook answers for yet — training custom visual models on user-provided samples at reasonable cost, running a workflow ecosystem where community-contributed ComfyUI pipelines could be called autonomously by agents and earn their creators revenue, giving agents context, tools, and identity that persist across sessions, and building all of it on an open-source foundation so the platform stays extensible.

FinanceFXEmpire

FXEmpire - Financial Markets & Trading Platform

FXEmpire operates a large financial publishing and market-data platform covering forex, commodities, stocks, indices, cryptocurrencies, and ETFs. The platform combines financial news and analysis with real-time market information, trading tools, calendars, screeners, and other data-driven features used by traders and investors. My involvement was focused specifically on the backend side of the platform, supporting the APIs and server-side functionality required to deliver reliable financial data and application features without representing the entire FXEmpire product as my work.